Flaring Work And Pipe Connection - Mitsubishi Electric PXZ-4F75VG Installation Manual

3. FLARING WORK AND PIPE CONNECTION

3-1. PRECAUTIONS FOR DEVICES THAT USE R32 REFRIGERANT
• U se C1220 copper phosphorus, for copper and copper alloy seamless pipes, to connect the refrigerant pipes. Use refrigerant pipes with the thicknesses
specified in the table to the below. Make sure the insides of the pipes are clean and do not contain any harmful contaminants such as sulfuric compounds,
oxidants, debris, or dust.
Always apply no-oxidation brazing when brazing the pipes, otherwise, the compressor will be damaged.
When installing, relocating, or servicing the unit, make sure that no substance other than the specified refrigerant (R32) enters the refrigerant
circuit.
Any presence of foreign substance such as air can cause abnormal pressure rise and may result in explosion or injury. The use of any refriger-
ant other than that specified for the system will cause mechanical failure, system malfunction, or unit breakdown. In the worst case, this could
lead to a serious impediment to securing product safety.
Pipe size (mm) ø6.35 ø9.52 ø12.7 ø15.88 ø19.05 ø22.2 ø25.4 ø28.58
Thickness (mm) 0.8 0.8 0.8
• D o not use pipes thinner than those specified above.
• U se 1/2 H or H pipes if the diameter is 19.05 mm or larger.
• B e sure to have appropriate ventilation in order to prevent ignition. Furthermore, be sure to carry out fire prevention measures that there are no dangerous
or flammable objects in the surrounding area.
3-2. FLARING WORK
1) Cut the copper pipe correctly with pipe cutter. (Fig. 1, 2)
2) Completely remove all burrs from the cut cross section of pipe. (Fig. 3)
• Aim the copper pipe downward while removing burrs to prevent burrs from
dropping in the pipe.
3) Remove flare nuts attached to indoor and outdoor units, then put them on pipe
having completed burr removal. (Not possible to put them on after flaring work.)
4) Flaring work (Fig. 4, 5). Firmly hold copper pipe in the dimension shown in the
table. Select A mm from the table according to the tool selected.
5) Check
• Compare the flared work with Fig. 6.
• If flare is noted to be defective, cut off the flared section and do flaring work
again.
A (mm)
Clutch
Pipe diameter Nut
Clutch
type tool
(mm) (mm)
type tool
for R32,
for R22
R410A
ø6.35 (1/4") 17
ø9.52 (3/8") 22
0 to 0.5 1.0 to 1.5
ø12.7 (1/2") 26
ø15.88 (5/8") 29
WARNING
1.0 1.0 1.0 1.0 1.0
Tightening torque
Wing nut
type tool N•m kgf•cm
for R22
13.7 to 17.7 140 to 180
1.5 to 2.0
34.4 to 41.2 350 to 420
49.1 to 56.9 500 to 580
2.0 to 2.5
73.5 to 78.5 750 to 800
Copper
pipe
Fig. 1
Copper pipe
Burr
Spare reamer
Pipe cutter
Clutch type
Fig. 3
Smooth all
around
Copper pipe
Die
Flare nut
Fig. 5
Good No good
Tilted Uneven Burred
Fig. 2
Flaring tool
Wing nut type
Fig. 4
Inside is shin-
ing without any
scratches.
Even length
all around
Fig. 6
en
9